Troubleshooting - Emerson Rosemount 975MR Reference Manual

Maintenance and troubleshooting

August 2019

Functional test procedure

Perform a functional test of the detector as described in

4.1.3

Keeping maintenance records

Emerson recommends that you record maintenance operations performed on a detector

in a log book. The record should include the following:

•

Installation date and contractor

•

Serial and tag number

•

Entries for every maintenance operation performed, including the description of the

operation, date, and personnel ID

If you send a unit to Rosemount or a distributer for service, include a copy of the

maintenance records.

4.2

This section is intended to be a guide to correct problems that may happen during normal

operation.

4.2.1

Fault relay at N.O.

LEDs off

0-20 mA at 0 mA

No power to the unit

Recommended actions

1. Check that the correct power is sent to the detector.

2. Check power polarity.

3. Check wiring in the detector.

4. Send the detector back for repairs.

4.2.2

Fault relay at N.O.

Yellow/amber LED flashes at 4 Hz.

0-20 mA at 0 mA

Detector fault

•

Low voltage

•

Faulty detector

Recommended actions

1. Check the voltage at the detector; verify at least 24 V at the detector terminal.

44

Reference Manual

00809-0100-4975

Internal detector

tests.

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